Korean American physician Jim Yong Kim took over as the new World Bank chief today.
He immediately challenged to ensure the euro zone crisis does not set back global poverty-fighting efforts.
"I'm humbled and inspired to take over today as president," Kim said at the doorstep of the Washington based global development lender as he launched into his first day on the job.
"I can't wait to get started," he said. "I've spent most of my adult life working in some of the poorest communities in the world," he added.
He pledged continuity in the bank's mission to help the poorest countries get on their feet, giving no hint of any changes to the work pattern set by his predecessor, Robert Zoellick.
"We will continue to do our work, with innovation, analytic rigour and with great passion, working in partnership with governments, civil society organisations, the private sector, and most importantly with the people living in poverty we aspire to serve," he said.
He acknowledged that he is taking over "at a pivotal moment for the global economy," with the euro zone crisis and economic slowdown in the largest countries impacting small, vulnerable economies around the world. He said the bank's staff are "passionate about the twin aims of boosting prosperity and eradicating poverty."
He takes over a sprawling development institution with a staff of 9,000 economists and policy specialists, and which made loans, grants and guarantees of $52.6 billion in the year to June 30.
Unlike the bankers, diplomats and economists who have run the World Bank in the past, Kim brings a background in medicine and a record developing programmes to fight diseases like HIV/AIDS and tuberculosis in poor countries.
His nomination to the post by President Barack Obama surprised many; his last job was as head of Dartmouth College, a small but prestigious university. But he has given little hint about any new directions he might plot for the bank.
52-year-old Kim was born in South Korea but was raised in the rural US Midwest. Kim - who goes by the name Jim Kim - attended Brown University and then Harvard Medical School, and following that earned a Harvard doctorate in anthropology.
He replaces Zoellick, the former US diplomat who took over in 2007 following the resignation of Paul Wolfowitz, another US diplomat whose tenure at the bank was cut short by scandal and conflict with bank staff. Zoellick restored the institution's image and helped it adjust quickly to the financial crisis that erupted in the US as he took over, as it sent shock waves through the global economy.
"The Bank is well positioned for future challenges," Zoellick had said in a statement on Friday. "Since I joined the institution, the Bank Group has committed over $300 billion - most of it to help countries overcome food and economic crises."
But Zoellick left Kim with a burning controversy as he departed: on Friday the bank cancelled a $1.2 billion infrastructure loan to Bangladesh citing strong evidence of "high level" corruption in the project and the lack of cooperation of authorities in investigating it.
"The World Bank cannot, should not, and will not turn a blind eye to evidence of corruption," it said in a statement.